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Targeted irradiation of nanostructures by a finely focused ion beam provides routes to improved control of material modification and understanding of the physics of interactions between ion beams and nanomaterials. Here, we studied radiation damage in crystalline diamond and silicon nanostructures using a focused helium ion beam, with the former exhibiting extremely long-range ion propagation and large plastic deformation in a process visibly analogous to blow forming. We report the dependence of damage morphology on material, geometry, and irradiation conditions (ion dose, ion energy, ion species, and location). We anticipate that our method and findings will not only improve the understanding of radiation damage in isolated nanostructures, but will also support the design of new engineering materials and devices for current and future applications in nanotechnology. [ABSTRACT FROM AUTHOR]

Highlights • Quantum electron microscopy (QEM) could reduce sample radiation damage. • QEM exploits an interaction-free measurement scheme in an electron cavity. • A linear electron cavity design is presented and characterized through simulation. • Approaches to correct spherical aberrations inside the cavity are proposed and validated through simulation. Abstract Quantum electron microscopy (QEM) is a measurement approach that could reduce sample radiation damage, which represents the main obstacle to sub-nanometer direct imaging of molecules in conventional electron microscopes. This method is based on the exploitation of interaction-free measurements in an electron resonator. In this work, we present the design of a linear resonant electron cavity, which is at the core of QEM. We assess its stability and optical properties during resonance using ray-tracing electron optical simulations. Moreover, we analyze the issue of spherical aberrations inside the cavity and we propose and verify through simulation two possible approaches to the problem. Finally, we discuss some of the important design parameters and constraints, such as conservation of temporal coherence and effect of alignment fields. [ABSTRACT FROM AUTHOR]

An effect of novel path generation algorithms for focused ion beam (FIB) milling is characterized in this paper. The basic concept of the suggested paths is to distribute the directional artifacts induced by the ion beam in order to overcome or minimize the inevitable drawbacks of FIB milling. Path generation algorithms, inspired by conventional mechanical machining, were applied to the FIB scanning paths. Our results showed that the scanning path had a significant influence on the product quality with negligible time loss. Numerous paths could be generated using the suggested approach, and eight representative paths were selected for experimental characterization with regard to the surface morphology, sputter yield, and artifacts formation. Our results showed that the backstitch raster and balanced raster exhibited the best quality in terms of low roughness and high squareness of the pocket. Conventional raster and serpentine scans created a large degree of defects, due to the material redeposition and varying ion incidence angle; however, these types of scan provided a high sputter yield. The proper scanning path can be determined with respect to the required squareness, surface roughness, or productivity. [ABSTRACT FROM AUTHOR]

Functional metal and ceramic thin films are widely used in application fields including electronics, biomedical devices, sensors, and actuators. The prevalence of polymers and organic materials is increasing, and low-temperature processing is becoming more desirable. Nanoparticle deposition is a room-temperature deposition process for metals and ceramics. Here, we report the growth of Sn, AlO, and TiO thin films under the same nanoparticle deposition process conditions. The material properties of the metal and ceramic layers were characterized, and multilayer stacks of Sn/AlO/Sn on silicon, TiO/AlO/Sn on silicon, and TiO/AlO on sapphire were fabricated. These results show that multilayer deposition can be achieved at room temperature simply by changing the materials while maintaining the same process conditions. Planarization was carried out following the growth of each layer, and a uniform thickness of each film in the multilayer stack was achieved. [ABSTRACT FROM AUTHOR]

Abstract: Focused ion beam (FIB) technology has become increasingly attractive for the fabrication of micro/nano structures for the purpose of the demands in industry and research. In this paper, various efforts to fabricate micro/nanoscale structure and geometrically complex structure are described, and their efficiency and structural stability are discussed. In order to fabricate such complex structures with micro/nanoscale features, the capability of the FIB is directly related to its destructive and constructive processes. It can also be used for modification and imaging in four basic modes. The fabrication processes, including both milling and deposition, are related to the precision fabrication of samples at the micro/nanoscale. By taking into account material processing rates, surface morphologies with nanoscale effects can be explained in detail. Finally, very recent developments using FIB will be reviewed. [Copyright &y& Elsevier]

Abstract: The performance of a field-emission scanning electron microscope (SEM) is primarily dependent on the characteristics of the electron source. Field-emission electron sources provide a high current density, which can be used to produce a beam that can be focused through an electrostatic lens. Using a single 〈111〉 crystalline tungsten tip, we fabricated and tested a field emitter having a 91nm radius and a stability under 14%. In this electron source, two electrostatic lenses consisting of 1st and 2nd anodes were designed and implemented and their performance dependence on variations in electrode shape, position, and applied voltage was investigated using a first-order finite-element method simulation. We also developed a line collector capable of measuring beam distribution and quantifying shifts in the electrical optical axis to characterize the behavior of a field-emitted electron beam as focused by an electrostatic optical system. [ABSTRACT FROM AUTHOR]

Abstract: Carbon structures were fabricated on silicon by focused ion beam-chemical vapor deposition using phenanthrene gas. The current of the 30keV gallium beam was set at 10.7pA. The relationship between the step size of the raster scan and the nanoscale structures obtained was investigated. Changes in step size from 4 to 85nm on scan areas of 300, 500, and 1000nm2 caused variations in the depletion and replenishment of adsorbed gas molecules, which in turn caused several nanoscale effects such as delocalization, round edge, slant sidewall, locally variation in deposition rate, discrete structure, and shadow effect in carbon structures. Changes in the deposition rates and surface morphologies of the carbon deposits were observed and discussed. [Copyright &y& Elsevier]

Abstract: Material addition using focused ion beam induced deposition (FIBID) is a well-established local deposition technology in microelectronic engineering. We investigated FIBID characteristics as a function of beam overlap using phenanthrene molecules. To initiate the localization of gas molecules, we irradiated the ion beams using a raster scan. We varied the beam overlap between −900% and 50% by adjusting the pixel size from 300nm to 15nm. We discuss the changes in surface morphologies and deposition rates due to delocalization by the range effect of excited surface atoms, the divided structure by continuous effect from the raster scan, enhanced localization by discrete effect from replenished gas molecules, the competition between deposition and sputtering processes, and the change in processing time with scan speed (smaller overlap case). [Copyright &y& Elsevier]

Efficient water electrolysis is one of the key issues in realizing a clean and renewable energy society based on hydrogen fuel. However, several obstacles remain to be solved for electrochemical water splitting catalysts, which are the high cost of noble metals and the high overpotential of alternative catalysts. Herein, we suggest Ni-based alternative catalysts that have comparable performances with precious metal-based catalysts and could be applied to both cathode and anode by precise phase control of the pristine catalyst. A facile microwave-assisted procedure was used for NiO nanoparticles anchored on reduced graphene oxide (NiO NPs/rGO) with uniform size distribution in ~1.8 nm. Subsequently, the Ni-NiO dual phase of the NPs (A-NiO NPs/rGO) could be obtained via tailored partial reduction of the NiO NPs/rGO. Moreover, we demonstrate from systematic HADDF-EDS and XPS analyses that metallic Ni could be formed in a local area of the NiO NP after the reductive annealing procedure. Indeed, the synergistic catalytic performance of the Ni-NiO phase of the A-NiO NPs/rGO promoted hydrogen evolution reaction activity with an overpotential as 201 mV at 10 mA cm−2, whereas the NiO NPs/rGO showed 353 mV. Meanwhile, the NiO NPs/rGO exhibited the most excellent oxygen evolution reaction performance among all of the Ni-based catalysts, with an overpotential of 369 mV at 10 mA cm−2, indicating that they could be selectively utilized in the overall water splitting. Furthermore, both catalysts retained their activities over 12 h with constant voltage and 1000 cycles under cyclic redox reaction, proving their high durability. Finally, the full cell capability for the overall water electrolysis system was confirmed by observing the generation of hydrogen and oxygen on the surface of the cathode and anode. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ZrCuSi sputtering target was produced by additive manufacturing (AM). • The optimal condition for the ZrCuSi nanocomposite coating was firmly established. • The ZrCuSiN nanocomposite thin films was well-transferred from the manufactured target. The present study demonstrates a simple and robust strategy for fabricating nanocomposite thin films with high quality using a multi-component ZrCuSi single target. The ZrCuSi target was produced by using computer numerical control (CNC) based direct energy deposition (i.e., 3D printing). The influence of the energy density on morphological features and porosity of the ZrCuSi target surface was closely examined at a certain range of the energy density (75–225 J/mm3). X-ray diffractometer (XRD) and scanning electron microscopy (SEM) were applied for confirming the presence of the preferable crystallographic orientation and elucidating the morphological features of the nanocomposite target. In addition, functional nanocomposite thin films deposited from the ZrCuSi target presented in the current study were characterized. A scratch test and field-emission SEM (FE-SEM) revealed the adhesion properties and the morphological features of the nanocomposite coatings. Therefore, this work is highly expected to provide a facile and robust way to fabrication of e multi-component functional targets based ZrN, thereby envisioning usefulness of the nanocomposite coatings for automotive engine parts and various other wear protection applications. [ABSTRACT FROM AUTHOR]

• Large-area electron phase plate fabricated with electron-beam lithography and reactive-ion-etching. • Electron diffraction with various electron energies and diffraction efficiencies. • Nullification of the direct beam in electron diffraction. • Diffractive imaging with the phase plate in a scanning electron microscope. Electron beams can acquire designed phase modulations by passing through nanostructured material phase plates. These phase modulations enable electron wavefront shaping and benefit electron microscopy, spectroscopy, lithography, and interferometry. However, in the fabrication of electron phase plates, the typically used focused-ion-beam-milling method limits the fabrication throughput and hence the active area of the phase plates. Here, we fabricated large-area electron phase plates with electron-beam lithography and reactive-ion-etching. The phase plates are characterized by electron diffraction in transmission electron microscopes with various electron energies, as well as diffractive imaging in a scanning electron microscope. We found the phase plates could produce a null in the center of the bright-field based on coherent interference of diffractive beams. Our work adds capabilities to the fabrication of electron phase plates. The nullification of the direct beam and the tunable diffraction efficiency demonstrated here also paves the way towards novel dark-field electron-microscopy techniques. [ABSTRACT FROM AUTHOR]

Hydrophobic surfaces have a wide range of applications, such as water harvesting, self-cleaning, and anti-biofouling. However, traditional methods of achieving hydrophobicity often involve the use of toxic materials such as fluoropolymers. This study aims to create controllable wettability surfaces with a three-dimensional geometry using a laser base powder bed fusion (PBF) process with commercially pure titanium (CP-Ti) and silicone oil as non-toxic materials. The optimal PBF process parameters for fabricating micropillar structures, which are critical for obtaining the surface roughness necessary for achieving hydrophobic properties, were investigated experimentally. After fabricating the micropillar structures using PBF, their surface energy was reduced by treatment with silicone oil. Silicone oil provides a low-surface-energy coating that contributes to the water-repellent nature of hydrophobic surfaces. The wettability of the treated CP-Ti surfaces was evaluated based on the diameter of the pillars and the space between them. The structure with the optimal diameter and spacing of micropillars exhibited a high contact angle (156.15°). A pronounced petal effect (sliding angle of 25.9°) was achieved because of the morphology of the pillars, indicating the controllability of wetting. The micropillar diameter, spacing, and silicone oil played crucial roles in determining the water contact and sliding angle, which are key metrics for surface wettability. [ABSTRACT FROM AUTHOR]

Patients with cartilage invasion in hypopharyngeal squamous cell carcinoma (HPSCC) would benefit from partial laryngopharyngectomy (PLP). The purpose of this study was to examine the treatment outcomes of PLP for HPSCC with cartilage invasion, with a focus on the oncological safety and the function preservation. We performed a retrospective review of 28 patients with HPSCC with thyroid or cricoid cartilage invasion who had undergone upfront surgery and were followed for more than one year between 1993 and 2019. Twelve patients treated with PLP (42.9%) and 16 patients treated with total laryngopharyngectomy (TLP) for cartilage invasion in HPSCC were identified. There was no significant difference in recurrence between the PLP group (7/12, 58.3%) and the TLP group (8/16, 50.0%) (p =.718). PLP was not associated with decreased five-year disease free survival (p =.662) or disease specific survival (p =.883) rates compared to TLP. Nine patients receiving PLP could be decannulated and retained intelligible speech (9/12, 75%). Gastrostomy tubes were placed in the PLP group (5/12, 42.9%) and TLP group (1/16, 6.2%) (p =.057). PLP appears to be a feasible option for the treatment of thyroid or cricoid cartilage invasion in HPSCC. [ABSTRACT FROM AUTHOR]

The overarching goal herein is to identify the factors dominating the performance of a‐IGZO‐based memristors. Despite the highest on/off ratio, greater than 104 with a preferred minimal set/reset bias achieved from a‐IGZO‐based memristors, it is observed that the switching performance and stability/reliability of the devices is significantly dominated by the VO·· density and metallization material, depending on their reactivity with IGZO. As the first governing factor, ensuring optimal VO·· concentration in the switching layer IGZO (VO··/OOx ratio 24.3% in this study) is crucial to obtain the tractable formation and rupture of conduction filament. Neither higher nor lower VO·· density than the optimized results in detrimental reliability issues, which may be ascribed to an uncontrollable filament in an abundant vacancy environment or a weak conducting path, respectively. As the second governing mechanism determining the memristor performance and reliability, it is suggested that metallization materials need to be carefully selected based on the thermodynamic redox potential and interfacial stability of the metallization material with IGZO. Metallization materials with larger reduction potential and interfacial stability are found to yield higher switching on/off ratio and greater device performance reliability. [ABSTRACT FROM AUTHOR]

Polydimethylsiloxane (PDMS) is widely utilised as a substrate for wearable (stretchable) electronics where high fatigue resistance is required. Cyclic loadings cause the rearrangement of the basic molecular structure of polymer chains, which leads to changes in the mechanical properties of the PDMS structure. Accordingly, it is necessary to investigate reliable mechanical properties of PDMS considering both monotonic and cyclic loading conditions. This study aims to present the mechanical properties of PDMS films against both monotonic and cyclic loading. The effects of certain parameters, such as film thickness and magnitude of tensile strain, on mechanical properties are also investigated. The test results show that PDMS films have a constant monotonic elastic modulus regardless of the influence of thickness and tensile loading, whereas a cyclic elastic modulus changes depending on experimental parameters. Several material parameters, such as neo-Hookean, Mooney–Rivlin, the third-order Ogden model, and Yeoh, are defined to mimic the stress–strain behaviours of the PDMS films. Among them, it is confirmed that the third-order Ogden model is best suited for simulating the PDMS films over the entire tensile test range. This research makes contributions not only to understanding the mechanical behaviour of the PDMS films between the monotonic and the cycle loadings, but also through providing trustworthy hyperelastic material coefficients that enable the evaluation of the structural integrity of the PDMS films using the finite element technique. [ABSTRACT FROM AUTHOR]

[Display omitted] NiFe-based layered double hydroxide (LDH) is a promising electrocatalyst for alkaline water electrolysis because of the low cost and earth abundance of Ni and Fe, as well as their characteristic layered structure resulting in high electrocatalytic performance. However, its hydrogen evolution reaction (HER) activity is still insufficient compared to existing catalysts. Additionally, the hydrothermal method, a common LDH fabrication method, can be time-consuming and complicated. Herein, we suggest a facile route for the preparation of HER catalyst within tens of seconds using one-pot electrodeposition with only a few ionic additives. A trace amount of Pt ion was added to enhance the HER performance and chloride (Cl−) ion was used to increase the specific surface area of the catalyst as well as to control the reduction of Pt ion for Pt-O bonding. Consequently, the 2.5 mmol Cl− ion treated NiFePt LDH (NiFePt_Cl LDH) requires an overpotential of only 52 mV to reach a current density of 100 mA cm−2 and significantly improved durability, with an overpotential increase of only 7 mV at 100 mA cm−2 after 1,000 cyclic voltammetry scans. [ABSTRACT FROM AUTHOR]

Objective: To survey cases of benign prostatic hyperplasia (BPH) among patients visiting urologists with lower urinary tract symptoms (LUTS) at general hospitals in Korea and to investigate treatment outcomes in current clinical practice. Methods: This was a multicenter, prospective study conducted in 18 urology centers in Korea. The symptoms of BPH were observed via the International Prostate Symptoms Score (IPSS), transrectal ultrasonography, uroflometry, prostate, specific, antigen, PSA) and postvoid residual volume at the baseline, 1 week, 4 weeks, 12 weeks, 24 weeks, and 52 weeks after initial evaluation. The patients were divided into three groups according to age (group I: 50-59; group II: 60-69; group III: 70 years or older). Results: Of the 1054 screened men, 966 were enrolled and 917 were diagnosed with BPH. Total IPSS and storage subscores were significantly higher in group III than in group II or I. By month 12, significant improvements on total IPSS and voiding subscores were demonstrated in group I over groups II and III (P = .02. 03, respectively). The incidence of dual combination therapy was significantly higher in the patients whose prostate volume was ≥30 mL and whose PSA was ≥1.5. Conclusion: At the initial visit, patients with LUTS/BPH, especially those who were relatively young, visited urologic centers because of to voidingsymptoms rather than storage symptoms. In contrast, elderly men who visited the urologic centers complained not only of voiding symptoms but also storage symptoms. However, at 12 months'' follow up, all of the age groups showed improvement in both storage and voiding symptoms. [Copyright &y& Elsevier]

The use of electron mirrors in aberration correction and surface-sensitive microscopy techniques such as low-energy electron microscopy has been established. However, in this work, by implementing an easy to construct, fully electrostatic electron mirror system under a sample in a conventional scanning electron microscope (SEM), we present a new imaging scheme which allows us to form scanned images of the top and bottom surfaces of the sample simultaneously. We believe that this imaging scheme could be of great value to the field of in-situ SEM which has been limited to observation of dynamic changes such as crack propagation and other surface phenomena on one side of samples at a time. We analyze the image properties when using a flat versus a concave electron mirror system and discuss two different regimes of operation. In addition to in-situ SEM, we foresee that our imaging scheme could open up avenues towards spherical aberration correction by the use of electron mirrors in SEMs without the need for complex beam separators. • An electrostatic electron mirror in an SEM reflects the beam towards the sample. • This imaging scheme could be beneficial to the in-situ SEM community. • We compare the micrographs when using a flat mirror and a curved aperture mirror. • This imaging scheme could lead to simpler mirror aberration correction in SEMs. [ABSTRACT FROM AUTHOR]

Abstract: Mimicking the designs from biological structures has been one of the most fascinating area of research due to their outstanding construction strategies to balance the performance and structure as per the demand of circumstances. In the present work, deposition of AgNPs on silicon substrate was carried out at room temperature by spraying nanoparticle (<100nm) at supersonic velocity through mimicking the sea shell structure of phylum Mollusca. The nano-layers of AgNPs were fabricated and characterized by assembling the Focused Ion Beam (FIB) and Scanning Electron Microscopy (SEM). Morphological analysis revealed that nanoparticles were deposited in resemblance of architecture of natural shell showing randomly oriented particles on the surface. [Copyright &y& Elsevier]

The microstructural evolutions in self-catalyzed GaAs nanowires (NWs) were investigated by using in situ heating transmission electron microscopy (TEM). The morphological changes of the self-catalyst metal gallium (Ga) droplet, the GaAs NWs, and the atomic behavior at the interface between the self-catalyst metal gallium and GaAs NWs were carefully studied by analysis of high-resolution TEM images. The microstructural change of the Ga-droplet/GaAs-NWs started at a low temperature of ∼200 °C. Formation and destruction of atomic layers were observed at the Ga/GaAs interface and slow depletion of the Ga droplet was detected in the temperature range investigated. Above 300 °C, the evolution process dramatically changed with time: The Ga droplet depleted rapidly and fast growth of zinc-blende (ZB) GaAs structures were observed in the droplet. The Ga droplet was completely removed with time and temperature. When the temperature reached ∼600 °C, the decomposition of GaAs was detected. This process began in the wurtzite (WZ) structure and propagated to the ZB structure. The morphological and atomistic behaviors in self-catalyzed GaAs NWs were demonstrated based on thermodynamic considerations, in addition to the effect of the incident electron beam in TEM. Finally, GaAs decomposition was demonstrated in terms of congruent vaporization. [ABSTRACT FROM AUTHOR]

This study presents a novel in-house modelling method called "Fibre Path Generator" and comprehensive parametric analyses on the mechanical performance of carbon fibre reinforced plastic (CFRP) with the fibre path along the principal stress direction, using both finite element (FE) simulations and experiments. The reliability of the developed CFRP model is validated through the fabrication of open-hole tensile test specimens using a co-extrusion composite 3D-printer, which demonstrated a highly compatible maximum tensile load with an error less than 3%. A comparative analysis is conducted to assess the mechanical performance of the CFRP specimen with principal stress fibre placement, which result shows that the maximum tensile load achieved is 172.84% higher than a CFRP model with uniaxial fibre placement. Furthermore, comprehensive parametric studies are carried out, varying the carbon fibre location and width-to-depth (w/D) ratio of the open-hole specimen, in order to evaluate the mechanical performance under the tensile loading. This study results provide useful insights to engineers when enhancing the mechanical performance of CFRP composite structures with effective continuous fibre placement. [ABSTRACT FROM AUTHOR]

This study explored the influence of pre-stretching temperature on the microstructural characteristics and deformation behavior of AZ61 magnesium alloy and its implications on grain growth during subsequent annealing. AZ61 alloy was stretched to 5% plastic strain along rolling (RD) and transverse direction (TD) at room (RT) and cryogenic temperature (−150 °C, CT) followed by annealing at 320 °C for 1 h to investigate the twinning and dislocation evolution and its consequent effect on the flow stress, plastic strain and strain hardening rate. Compared to RT-stretched samples, significant improvement in yield stress, strain hardening rate and moderate reduction in elongation to failure were witnessed for CT-stretched samples along RD and TD. The subsequent EBSD analysis revealed the increased fraction of fine {10−12} twins and nucleation of multiple {10−12} twin variants caused by higher local stress concentration at the grain boundaries in CT-stretched samples as manifested by the kernel average misorientation. This higher twin fraction and twin-twin interaction imposed the strengthening by restricting the mean free path of dislocations leading to higher flow stress and strain hardening rate. During annealing of the RT/CT-stretched samples, the residual strain energy and twin boundaries were decreased due to static recovery leading to a coarse-grained twin-free microstructure. Strain induced boundary migration (SIBM) was found to be the predominant mechanism governing the grain growth during annealing via movement of high angle grain boundaries. • Effect of pre-stretching at room and cryogenic temperature was investigated. • Annealing treatment was carried out to witness the grain growth mechanism in stretched samples. • CT-stretched samples displayed significant improvement in yield strength. • Strain induced boundary migration was found to be the predominant mechanism governing the grain growth. [ABSTRACT FROM AUTHOR]

We report the novel oxygen evolution reaction (OER) catalyst based on cobalt incorporated hydroxyapatite (CoHAP). Our catalyst is prepared on the surface of hydroxyapatite by ion exchange reaction in Co2+ aqueous solution. The cobalt content is approximately 1 wt. % based on ICP‐AES and XPS experiments. XRD, TEM, EDX experiments suggest that individual cobalt ions are adsorbed on the HAP surface in non‐aggregated manner. The cyclic voltammetry (CV) of CoHAP exhibits a weak oxidation peak at 1.10 V which is comparable to CV of in‐situ formed Co−Pi in previous literature. Tafel slope is approximately 80 mV/decade which is independent on the loading amount of CoHAP. The Faradaic efficiency is 94 % measured by quantitative analysis of O2 using gas chromatography. Bulk electrolysis verifies that CoHAP can be utilized OER catalyst at neutral pH with high stability. Our preparation method using hydroxyapatite as a solid phase phosphate source offers a new strategy to fabricate the OER catalysts. [ABSTRACT FROM AUTHOR]

In this paper, we present a review of machine health managements for the smart factory. As the Industry 4.0 leads current factory automation and intelligent machines, the machine health management for diagnostic and prognostic purposes are essential, and their importance is getting more significant for the realization of the smart factory in the Industry 4.0. After brief introductions to important concepts and definitions composing smart factory and Industry 4.0, the developments in maintenance strategies towards Prognostics and health management (PHM) of machines are summarized. The review of machine health managements is followed, classifying the references by the monitoring components, types of measurements, as well as PHM tools and algorithms. 94 existing articles are reviewed and summarized in this regard. The implementations of machine health managements within the smart factory are discussed in terms of data connectivity, communications, Cyber-physical system (CPS) and virtual factory, relating them to Internet of things (IoT), cloud computing, and big data management. [ABSTRACT FROM AUTHOR]

As a renewable energy harvesting method, interest in piezoelectric energy harvesting has increased significantly. Despite the piezoelectric energy-harvesting technology expanding its area to the flexible (elastic, amendable) devices, striking use or application of the technology is hardly found in the market. Here, we report a novel flexible piezoelectric energy harvester fabricated by using an additive manufacturing process, which enables both effective and customized manufacturing technique. By taking advantages of additive manufacturing, further application of the piezoelectric energy-harvesting technology is highly expected. Particles of BaTiO3, a ceramic with a large piezoelectric constant, were mixed with polyether block amide elastomer to form a flexible piezoelectric composite. The energy harvester was fabricated using an additive manufacturing process, by printing the piezoelectric composite on a laser-patterned flexible Indium-tin-oxide–coated polyethylene terephthalate substrate. Performance of fabricated energy harvester was evaluated by applying a mechanical stress to the energy harvester; voltage and current output were 2 V and 40 nA, respectively. An analytical model of the piezoelectric energy harvester was developed and discussed to explain the form of the voltage waveforms in response to the applied stress. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the efficacy of early management of post-thyroidectomy unilateral vocal cord palsy (UVCP) and the clinical utility of the thyroidectomy-related voice questionnaire (TVQ) when planning UVCP treatment. The study group comprised 48 consecutive patients diagnosed with UVCP after thyroidectomy. Laryngoscopic examination and voice analysis were conducted, and the TVQ was administered pre-thyroidectomy and at 2 weeks and 1, 3, 6, and 12 months post-thyroidectomy. Twenty-five patients with aspiration symptoms and severe vocal difficulties received injection laryngoplasty, and 23 with no aspiration symptoms and relatively mild vocal difficulties underwent voice therapy. We performed a video fluoroscopic swallowing study on each patient 2 weeks after thyroidectomy and 1 month following the procedure. The average total TVQ scores 2 weeks post-thyroidectomy were 51.92 ± 11.42 in the injection laryngoplasty group and 35.78 ± 12.99 in the voice therapy group. Both subjective and objective parameters improved significantly at 1 month after treatment and continued to improve slowly over the next 12 months ( p < 0.01) in both groups. TVQ scores were significantly lower in the injection laryngoplasty group than in the voice therapy group 1 month post-intervention ( p < 0.01). At the study end point, the greatest improvement in subjective symptoms occurred in temporary VCP patients who underwent injection laryngoplasty. The optimal TVQ score cut-off distinguishing the two groups was 45 (68.0 % sensitivity, 78.3 % specificity). In conclusion, early management following timely diagnosis of post-thyroidectomy UVCP can improve symptoms within 1 month. Moreover, application of TVQ will aid clinicians to plan treatment for postoperative VCP patients. [ABSTRACT FROM AUTHOR]

Histone modification plays a pivotal role on gene regulation, as regarded as global epigenetic markers, especially in tumor related genes. Hence, chemical approaches targeting histone-modifying enzymes have emerged onto the main stage of anticancer drug discovery. Here, we investigated the therapeutic potentials and mechanistic roles of the recently developed histone deacetylase inhibitor, CG200745, in non-small cell lung cancer cells. Treatment with CG200745 increased the global level of histone acetylation, resulting in the inhibition of cell proliferation. ChIP-on-chip analysis with an H4K16ac antibody showed altered H4K16 acetylation on genes critical for cell growth inhibition, although decreased at the transcription start site of a subset of genes. Altered H4K16ac was associated with changes in mRNA expression of the corresponding genes, which were further validated in quantitative RT-PCR and western blotting assays. Our results demonstrated that CG200745 causes NSCLC cell growth inhibition through epigenetic modification of critical genes in cancer cell survival, providing pivotal clues as a promising chemotherapeutics against lung cancer. [ABSTRACT FROM AUTHOR]

Subsea pipelines are generally used to transfer hydrocarbons from ultra-deep seawater to facilities on the shore. Typically, sandwich pipelines are filled with polymeric cores for thermal insulation, with structural reinforcements also used as a deep-water application. Sandwich pipelines are subjected to either monotonic or cyclic loads, such as bending moment, buckling, internal and external pressures during their installation or operation. It is necessary to evaluate the cyclic plasticity of sandwich pipelines under complex loading combinations to prevent structural failures caused by applied loads. In this research, limit load and shakedown analyses of sandwich pipes subjected to complicated cyclic thermo-mechanical loadings are conducted using a Linear Matching Method (LMM). Temperature-dependent material properties are employed to simulate actual pipeline behaviour, and an elastic perfectly plastic model is considered with regard to geometric non-linearity issues. Numerical results are validated via a full cyclic incremental analysis, also known as a step-by-step analysis. Moreover, comprehensive parametric studies are conducted with respect to changes in the geometry of sandwich pipelines. This research presents valuable insights into the most severe loading types and combinations affecting the structural integrity of sandwich pipelines. In addition, allowable load boundaries against existing geometric parameters can be determined. • The structural integrity of sandwich pipelines is analysed by Linear Matching Method. • Shakedown and limit load boundaries have been constructed against cyclic loadings. • Cyclic in-plane bending severely affects the structural integrity of the pipelines. • Parametric study demonstrates change in diameter affects integrity more than in thickness. [ABSTRACT FROM AUTHOR]

Conclusion: Median 18F-FDG PET/CT maximum standardized uptake values (SUVmax) cut-off values of 7.9 or greater were associated with high-risk human papillomavirus (HPV) negativity in patients with hypopharyngeal squamous cell carcinoma (HPSCC). Furthermore, median 18F-FDG PET/CT SUVmax cut-off values of 7.9 or greater and high-risk HPV negativity were associated with adverse outcomes. Objectives: We studied the association and the potential prognostic significance of 18F-FDG PET/CT and high-risk HPV status in HPSCC. Methods: The medical records of 45 patients who underwent 18F-FDG PET/CT for HPSCC before surgery were reviewed. High-risk HPV in situ hybridization was performed to detect HPV infection. Results: The median SUVmax was 9.91 ± 4.91 (range 1.9-22.1) and the positive rate of high-risk HPV in situ hybridization was 11% (5 of 45). The SUVmax values of negativity for the high-risk HPV subtypes (10.47 ± 4.87) and positivity (5.48 ± 2.45) were found to be significantly different ( p = 0.030). The SUVmax cut-off value for differentiating negativity for the high-risk HPV subtypes from positivity was 7.9, with a sensitivity of 65% and a specificity of 80%. The 5-year disease-specific survival rate (DSSR) in our cohort was 57%. Patients with an SUVmax value higher than 7.9 ( p = 0.005) and high-risk HPV negativity ( p = 0.047) had decreased 5-year DSSR. [ABSTRACT FROM AUTHOR]

F-FDG PET/CT is clinically useful in the initial staging and follow-up of patients with head and neck squamous cell carcinoma (HNSCC). We studied the potential prognostic significance of preoperative F-FDG PET/CT in HNSCC. The medical records of 294 patients who underwent preoperative F-FDG PET/CT for HNSCC were retrospectively reviewed. The median SUV of the primary lesions (SUV) and cervical lymph nodes (SUV) was 7.98 ± 5.04 (range 1.2-28.7) and 3.34 ± 3.70 (range 1.0-20.4), respectively. There was a significant difference between with and without recurrence in SUV (11.14 ± 5.36 vs. 6.78 ± 4.35, p < 0.001) and SUV (5.60 ± 4.22 vs. 1.75 ± 1.46, p < 0.001). The cut-off values of SUV and SUV in the context of recurrence and cancer-related death were 8.5 and 3.5. The 5-year disease-free survival of patients with SUV < 8.5 and SUV < 3.5 was 79 and 79 %, respectively, whereas that of patients with SUV ≥ 8.5 and SUV ≥ 3.5 was 39 and 30 %, respectively. Multivariate analysis confirmed the significant association between 5-year disease-free survival and SUV ≥ 8.5 (hazard ratio (HR) 2.68, p < 0.001) and SUV ≥ 3.5 (HR 2.29, p = 0.007). Furthermore, SUV ≥ 8.5 (HR 3.20, p = 0.012) and SUV ≥ 3.5 (HR 2.14, p < 0.001) were associated with 5-year overall survival. F-FDG PET/CT cut-off values of SUV ≥ 8.5 or SUV ≥ 3.5 are associated with a recurrence and survival in HNSCC. [ABSTRACT FROM AUTHOR]

Conclusion: High-risk human papillomavirus (HPV) infection was significantly related to lymph node size in patients with single node metastasis of oral and oropharyngeal cancer. Objective: The purpose of this study was to examine the relationship between high-risk HPV infection and lymph node size in patients with single node metastasis of oral and oropharyngeal carcinoma. Methods: This study included 48 patients with oral and oropharyngeal carcinoma. Pathologic lymph node stages comprised 36 N1 and 12 N2a. Results: High-risk HPV in situ hybridization was positive in 29% of patients (14/48). Of those patients with high-risk HPV, there was a significant difference ( p = 0.008) between oral (9.5%) and oropharyngeal (44.4%) cancers. Average lymph node diameter was 20.7 ± 12.6 mm (range 5-54 mm). We found a positive correlation between high-risk HPV status and lymph node size ( p = 0.018). Mean lymph node diameter in high-risk HPV-positive cases was 27.3 ± 13.1 mm and 18.0 ± 11.5 mm in high-risk HPV-negative cases. Extracapsular spread ( p = 0.030) and cystic nodal metastases ( p = 0.019) were also significantly related to lymph node size. High-risk HPV negative status ( p = 0.043), advanced tumor stage ( p = 0.009), and extracapsular spread ( p = 0.038) all had significant adverse effects on 5-year disease-specific survival. [ABSTRACT FROM AUTHOR]

Conclusion: 18F-FDG PET/CT is a useful technique for the evaluation of paraglottic space invasion and lymph node metastasis in patients with supracricoid partial laryngectomy (SCPL). Primary SUVmax values (using 7.0 as a cut-off) and nodal SUVmax values (using 2.2 as a cut-off) are important for recurrence and poor prognosis. Objectives: The purpose of this study was to evaluate the usefulness of 18F-FDG PET/CT for paraglottic space invasion and lymph node metastasis and the prognostic significance in SCPL. Methods: The medical records of 42 patients who underwent 18F-FDG PET/CT for SCPL before surgery were reviewed. Results: The median primary SUVmax was 6.63 ± 5.07 and the median nodal SUVmax was 1.25 ± 1.86. The primary SUVmax values with paraglottic space invasion (8.34 ± 5.92) and without (4.57 ± 2.74) were significantly different ( p = 0.015). The 18F-FDG PET/CT had an accuracy of 87% for the identification of cervical metastases on a level-by-level basis. A median primary SUVmax value of 7.0 and nodal SUVmax of 2.2 were associated with recurrence ( p = 0.022 and p = 0.009, respectively) and 5-year disease-specific survival ( p = 0.021 and p = 0.041, respectively). [ABSTRACT FROM AUTHOR]

Background: High-risk human papillomavirus (HPV) is an oncogenic virus that causes oropharyngeal cancers, and it has a favorable outcome after the treatment. Unlike in oropharyngeal cancer, the prevalence and role of high-risk HPV in the etiology of hypopharyngeal squamous cell carcinoma (HPSCC) is uncertain. Objective: The aim of the present study was to evaluate the effect and prognostic significance of high-risk HPV in patients with HPSCC. Methods: The study included 64 subjects with HPSCC who underwent radical surgery with or without radiation-based adjuvant therapy. Primary tumor sites were the pyriform sinus in 42 patients, posterior pharyngeal wall in 19 patients, and postcricoid area in 3 patients. High-risk HPV in situ hybridization was performed to detect HPV infection. Results: The positive rate of high-risk HPV in situ hybridization was 10.9% (7/64). There was a significant difference in the fraction of positive high-risk HPV among pyriform sinus cancer (16.7%), posterior pharyngeal wall cancer (0%), and postcricoid area cancer (0%) (p = 0.042). The laryngoscopic examination revealed a granulomatous and exophytic appearance in 85.7% (6/7) of patients with high-risk HPV-positive pyriform sinus cancer, but in only 31.4% (11/35) of patients with high-risk HPV-negative pyriform sinus cancer (p = 0.012). Significant correlations were found between positive high-risk HPV and younger age (p = 0.050) and non-smoking status (p = 0.017). HPV-positive patients had a significantly better disease-free survival (p = 0.026) and disease-specific survival (p = 0.047) than HPV-negative patients. Conclusions: High-risk HPV infection is significantly related to pyriform sinus cancer in patients with HPSCC. [ABSTRACT FROM AUTHOR]

Conclusion: Factors that affected prognosis were T stage and extracapsular spread in patients that underwent primary surgery with postoperative radiotherapy for pN2 head and neck carcinoma. Objectives: The purpose of this study was to examine treatment outcomes and define prognostic factors for pN2 head and neck carcinoma. Methods: A total of 209 patients underwent surgery with postoperative radiotherapy between 1994 and 2011. Primary tumor sites were the oropharynx ( n = 70), hypopharynx ( n = 48), larynx ( n = 47), and oral cavity ( n = 44). There were 21, 83, 60, and 45 patients with stage T1 to T4 cancers, respectively. The N stages were 20 N2a, 129 N2b, and 60 N2c. Results: The recurrence rate was 40% (83/209) over a mean observation period of 39 months. The 5-year disease-free survival (DFS), disease-specific survival (DSS), and overall survival (OS) rates in our cohort were 44%, 60%, and 56%, respectively. The presence of advanced T stage or extracapsular spread had a significant adverse effect on 5-year DFS, DSS, and OS rates according to Kaplan-Meier survival curves. Multivariate Cox regression analysis confirmed the significant association between 5-year DSS rate and advanced T stage (hazard ratio (HR), 2.20; 95% confidence interval (CI), 1.26-3.82; p = 0.005) and extracapsular spread (HR, 2.29; 95% CI, 1.24-4.21; p = 0.008). [ABSTRACT FROM AUTHOR]

Conclusion: Median maximum standardized uptake (SUVmax) cut-off values of FDG PET/CT higher than 3.85 were found to be associated with a greater risk cervical lymph node metastasis with extracapsular spread (ECS) in patients with oropharyngeal squamous cell carcinoma (OPSCC). Objectives: The purpose of this study was to evaluate the use of FDG PET/CT for the identification of ECS and to establish its histologic correlates in OPSCC. Methods: The medical records of 78 patients who underwent FDG PET/CT for OPSCC before surgery were reviewed. Results: ECS was present in 42% (42/69) of dissected necks and in 51% (54/106) of dissected cervical levels. The SUVmax values of cervical lymph nodes with and without ECS were found to be significantly different (6.73 ± 3.78 vs 3.02 ± 2.24, p < 0.001). The SUVmax cut-off value for differentiating necks with ECS from those without ECS was 3.85. The presence of ECS ( p = 0.036) and median SUVmax (using 3.85 as a cut-off) ( p = 0.037) were found to have a significant adverse effect on 5-year disease-specific survival by univariate analysis. The multivariate analysis showed a significant association of 5-year disease-specific survival with ECS (hazard ratio (HR) = 32.3 in cervical metastasis with ECS, p = 0.012; and HR = 19.6 in cervical metastasis without ECS, p = 0.024). [ABSTRACT FROM AUTHOR]

We report the oxygen evolution reaction (OER) catalyst composed of cobalt–calcium phosphate on reduced graphene oxide (CoCaP/rGO). Our catalyst is prepared by the anodic electrolysis of calcium phosphate/rGO mixture loaded on indium-tin-oxide (ITO) in Co2+ aqueous solution. TEM, XPS and XRD experiments confirm that the crystal phase of calcium phosphate (CaP) is transferred into an amorphous phase of calcium oxide with phosphate (5.06 at%) after anodic electrolysis. Additionally, the main cation component of calcium is replaced by cobalt ion. The current–voltage characteristics of CoCaP/rGO showed a shoulder peak at 1.10 V vs. NHE, which originated from Co2+ to higher oxidation states (Co3+ or Co4+) and a strong wave from water oxidation higher +1.16 V vs. NHE at neutral condition (pH 7). CoCaP and CoCaP/rGO showed 4.8 and 10 mA/cm2 at 0.47 V of overpotential, respectively. The enhanced OER catalytic activity of CoCaP/rGO arises from the synergetic interaction between the amorphous phase of CoCaP and electric conducting graphene sheets. [ABSTRACT FROM AUTHOR]